A semiconductor device of this type includes a voltage-control type semiconductor element that is made up of an IGBT (Insulated Gate Bipolar Transistor), a power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), or the like.
As described in, for example, JP 2004-36438 A, when such a semiconductor device is used as an ignition device of an internal combustion engine mounted to a vehicle, one end of the primary side of an ignition coil is connected to a battery and the other end is grounded via the voltage-control type semiconductor element. When the voltage-control type semiconductor element is to be turned on, an ignition signal of a predetermined voltage is supplied, as a gate signal, from an external control device to the gate of the voltage-control type semiconductor element through a gate resistor to cause a gate voltage to rise and the voltage-control type semiconductor element to be turned on.
On the other hand, when the voltage-control type semiconductor element is to be turned off, electric charges accumulated in the gate capacitance of the voltage-control type semiconductor element are discharged to the external control device side.
The semiconductor device includes protection control circuits, such as an operation level setting circuit, a thermal shut-off circuit, and a current limit circuit, that operate using the ignition signal as a power supply voltage.
As described in JP 2016-1635 A, to compensate an instantaneous drop in the power supply voltage supplied to digital circuits, analog circuits, and a power device drive circuit that constitute the protection control circuits, adding a low pass filter circuit to each of the circuits has been proposed.